This invention relates to a unique method of teaching transmitter codes to a receiver, such as a remote vehicle door entry receiver, wherein the codes are transmitted to a receiver directly over the communication bus line in the vehicle.
Vehicle door remote entry systems are becoming increasingly popular. Originally, these systems utilized any one of a relatively small number of fixed identification (i.d.) codes. Thus, the receiver and transmitter could be quickly and easily taught corresponding codes in a bulk programming method where many receivers were taught the same transmitter. However, this fixed code system has some undesirable security features. When there are only a small number of available codes, then the possibility of a criminal entering a vehicle by using a like transmitter is greatly increased. For that reason it has become desirable to manufacture transmitters which contain ID codes that have been randomly generated, when used with such transmitters, the receiver must xe2x80x9clearnxe2x80x9d the actual ID codes so that it will know which transmitters belong to the system.
Each transmitter has the identification code, which is comprised of several bytes of information, programmed within its own software.
Presently, the known method of programming the receiver includes providing a series of complicated signals based on actuation of vehicle switches to tell the receiver to enter a programming mode. The receiver then receives and stores the signal from the transmitter. Once the receiver has completed the programming mode, it is able to recognize the dedicated transmitters that have been associated with the receiver.
One difficulty with this system is that the procedure for signalling the receiver to enter the programming mode is relatively complex. The signals cannot be simple, or the operator may accidentally move the receiver into the programming mode. Thus, it is typical that the manufacturer of the receiver and transmitter systems would perform the manipulation of the system, since it is complex, to put the receiver in the programming mode. The programmed security system is then transported to the vehicle manufacturer for assembly into a vehicle. In many cases, the receiver is incorporated into a junction block for the vehicle, which is provided by a second automotive supplier. Thus, the remote entry system receiver must first be programmed, then sent to the second supplier, and incorporated into the junction block. The assembled junction block is then transported to the vehicle supplier.
With this procedure, the particular transmitters must be maintained with the receiver. To this end, assemblers have typically bundled the transmitter with the receiver. As an example, the transmitters may be taped or otherwise attached to the receiver body during shipment. Once the receiver is associated with the vehicle, the transmitters are stored in the vehicle, often being placed in the glove compartment.
In the past, the transmitters have sometimes become misplaced. This presents a problem as the complex learning for the receiver must then be repeated. It is a desire of the final vehicle assembler to minimize any complications. The requirement of having to associate the transmitters with the receiver presents unwanted complications to the vehicle assembler.
In a disclosed embodiment of this invention, the signal to place the receiver in programming mode is sent through a communication bus line associated with the vehicle system, after the receiver has been mounted onto the vehicle. A simple switching procedure is utilized to place the receiver in its programming mode, and the receiver is then taught the codes for the particular transmitters. With this method, the receivers need not be bundled with the transmitter until after the final vehicle assembly. Instead, transmitters may be selected at a late assembly line location and then programmed into the receiver. This reduces complications for the vehicle assembler.
In one preferred embodiment, the diagnostic box, which is typically connected to the bus line to perform a final quality check of vehicle electrical systems, is utilized to send the receiver the signal to move into programming mode. The diagnostic box is preferably modified to include a start or program button that sends the signal. The diagnostic box is provided with a harness that is connected to the computer bus line. When testing is complete the box is disconnected and the vehicle component wire harness is attached to the bus line.
In a preferred embodiment, the diagnostic box is also provided with its own receiver. The operator transmits a signal from a first transmitter to the diagnostic box receiver where it is captured and stored. Subsequent transmitter signals are also captured and stored at the diagnostic box receiver. Once all required signals have been captured, the diagnostic box sends the code over the communication bus line to the receiver. The diagnostic box is preferably provided with a series of prompt lights to assist the operator in performing these required steps in the proper sequence.
With the diagnostic box based receiver, noise may be de-tuned from other machines on the assembly line, and from adjacent assembly lines, where programming of other receivers may be taking place. In one embodiment, the antenna associated with the receiver on the diagnostic box is made to only accept a signal from very close range. As an example, that antenna could be designed such that it would only accept a signal within a range of three feet. In this way, noise from adjacent machinery or assembly lines would not effect the transmission or reception of the signal. The same limited range may not be practical for the vehicle based receiver that is to receive the signal from the driver, and thus typically needs to function at a longer range.
In a second embodiment, the diagnostic box does not include the receiver nor the prompt lights. Instead, the diagnostic box is provided only with the switch to initiate a programming signal. The operator actuates the switch and a signal is sent over the bus line to tell the receiver to enter a programming mode. The operator then transmits the codes directly to the vehicle mounted receiver in the ECU which captures and records the codes.
Once programming is complete the diagnostic harness is disconnected.
In addition, a junction box which may include the ECU for the vehicle communicates with the communication bus line to send and receive electrical signals to components and systems on the vehicle. The receiver for the remote vehicle door entry systems is incorporated into this junction box, and communicates with the bus line. The receiver is operable to receive a signal to enter a programming mode over the bus line.
These and other features of the present invention can be best understood from the following specification and drawings, of which the following is a brief description.